Experiment Definition and 1000 Threads

An experiment is a procedure carried out to support or refute a hypothesis. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a particular factor is manipulated. Experiments vary greatly in goal and scale, but always rely on repeatable procedure and logical analysis of the results. There also exists natural experimental studies.
A child may carry out basic experiments to understand how things fall to the ground, while teams of scientists may take years of systematic investigation to advance their understanding of a phenomenon. Experiments and other types of hands-on activities are very important to student learning in the science classroom. Experiments can raise test scores and help a student become more engaged and interested in the material they are learning, especially when used over time. Experiments can vary from personal and informal natural comparisons (e.g. tasting a range of chocolates to find a favorite), to highly controlled (e.g. tests requiring complex apparatus overseen by many scientists that hope to discover information about subatomic particles). Uses of experiments vary considerably between the natural and human sciences.
Experiments typically include controls, which are designed to minimize the effects of variables other than the single independent variable. This increases the reliability of the results, often through a comparison between control measurements and the other measurements. Scientific controls are a part of the scientific method. Ideally, all variables in an experiment are controlled (accounted for by the control measurements) and none are uncontrolled. In such an experiment, if all controls work as expected, it is possible to conclude that the experiment works as intended, and that results are due to the effect of the tested variables.

View More On Wikipedia.org
  1. Z

    B Advice For My Physics Experiment

    So for my curriculum I have to do a physics experiment and write a 2000 word essay on it. For my experiment, I'm planning to wrap a string with a ball attached to it n number of times around a pole and measure the time taken for it to unwind by changing variables such as the radius of the pole...
  2. B

    B Trying to understand the double-slit experiment

    Has anyone ever thought that the wave pattern on the screen is not because the particle is a wave. There is no reason that the wave appearance could not be due to a photon being distributed in this fashion and still be a particle while both slits are open. You have a different distribution with...
  3. MadMartigan

    Calculating the angle of a double-slit experiment

    Homework Statement So, my physics professor has been behind all semester long and basically taught the entire light wave and optics chapters in a single day and explained absolutely nothing, hence massive confusion on the following problem:[In a double-slit experiment, the slit separation is...
  4. W

    How to linearise this equation for experiment?

    Homework Statement I have a rotating platform that spins as a mass attached to a wheel rotates the larger platform. The mass accelerates to the ground which spins the platform essentially. I am trying to calculate the moment of inertia of another mass which will be attached to the rotating...
  5. M

    A Double slit experiment wave interference?

    Hi, my answer is about the double slit experiment: the interference is observable with the water waves, them are particle in movment, but when we observe it with the electrons, what is the medium for those waves? Are the particles made of matter between the gun and the slits? Or is it something...
  6. MaxFieg

    I Wu Experiment and Parity Violation

    I have a question concerning the nature of Ms. Wu's experiment confirming parity violation. I'm very familiar with this experiment and its outcomes, but the setup of the experiment itself, alludes me. Wu found that the electron's emitted from the Cobalt-60 atom always went in the direction...
  7. pchu

    Casimir force experiments under environmental EM noises?

    I've always been curious about how rigorous are the Casimir force measurements carried out, because a couple of years ago I read some news about people inventing perpetual motion machine which turned out to be draining power from environmental EM noises, say, radio station, wifi, 3G/4G that keep...
  8. infinitebubble

    I CERN n_TOF experiment: 'Age of the Universe'

    Exciting to see CERN coming back to experiments. Of interest is the n_TOF instruments to study the estimated age of the universe through neutron-induced reactions of the 'Rhenium-Osmium'cosmo-chronometer. Anyone have a more detail explanation of how this device works? The rhenium-osmium isotopic...
  9. B

    I Data from a delayed choice quantum eraser experiment

    Hello! Does anyone here have raw data from a delayed choice quantum eraser experiment that you wouldn't mind sharing? Ideally, data from all the detectors, not just coincidence counts that the analysis usually focuses on? Or, are you aware of any data repository where data from quantum physics...
  10. B

    A How possible is LDA DOS not consistent with experiment?

    Usually one would expect through \sigma=ne^2 \tao/m and DOS~1/m to argue that \sigma ~ DOS around Fermi surface. This seems to be a quite fundamental argument and should be expected to hold most of the time. For a quality check, does anybody have experience on how often LDA gives consistent DOS...
  11. S

    B Double slit experiment - doesn't measurement affect photons?

    All these videos and articles about the Double Slit Experiment say that if we "look" where the single photons go, they act like particles and if we don't "look" they act like waves, creating the interference pattern... BUT What does it mean to "look"? We're not using our eyes or any camera...
  12. davidge

    Thought experiment: charged particles

    Suppose we have two charged particles on the laboratory and two observers A and B. ##A## is inside one of the charges (never mind how) ##B## is sitting at the laboratory In the lab reference frame we accelerate the particles. According to ##A## there will be only electric attraction or...
  13. Fred Hill

    Driving force of a car experiment

    Homework Statement A car driving at a speed of 60km/h at a horizontal road. The car accelerates to 65km/h, and then the engine gets deactivated. The speed then decreases to 55km/h in a time of 7,2 seconds. The mass of the car is 1450 kg(the car, passenger etc...) Homework Equations What is the...
  14. CassiopeiaA

    B Conservation of Total Spin in the Stern Gerlach Experiment

    I just started reading Stern Gerlach Experiment and this thought crossed my mind. Totally a hypothetical question. If I pass an electron and positron through separate SG apparatuses, I will know in which spin state each particle has collapsed. But afterwords I let electron-positron pair...
  15. M

    Setting up a circuit to drive a Laser Diode

    Hello fellow physics friends (alliteration: always a strong opener). I am writing today because I find myself struggling to complete something which ostensibly doesn't seem that difficult to the average physics undergrad working in a lab. However, electronics and circuits are definitely a...
  16. dongwoo

    How is the spin state determined after the first Stern-Gerlach experiment?

    Homework Statement problem no.3 Homework Equations <ΨㅣΩㅣΨ> The Attempt at a Solution I used <ΨㅣΩㅣΨ> and but I don't find solution lΨ(t)>=? I need help...
  17. S

    Thomas Young's Double-Slit Experiment Problems

    Homework Statement Determine the wavelength of light being used to create the interference pattern in 3 different ways from the given data. -The angle to the 8th maximum is 1.12° -The distance from the slits to the screen is 302 cm -The distance from the first minimum to the fifth minimum is...
  18. B

    Stern-Gerlach experiment Problem

    Homework Statement Homework EquationsThe Attempt at a Solution (a) : There is no interference. (b) : Interference And i don't know how to approach (c), (d)
  19. M

    What are the errors in Young's Double Slit experiment?

    Homework Statement I am having troubles trying to figure out systematic and random errors when conducting Young's double slit experiment. Homework Equations NA The Attempt at a Solution I have found one error which could be correct, it is the fact that the laser was not at right angles with...
  20. brainpushups

    A simple collision experiment and a question

    I recently came across https://www.physics.uoguelph.ca/~jlhunt/morph/5exp.pdf paper in The Physics Teacher that describes a handful of experiments which can be performed with common materials. The collision experiment in particular caught my eye because it seems like most collision experiments...
  21. dylanreynolds1

    I Thought Experiment Contradiction: Find the Answer

    Hello all, I have a question that's been bothering me the last few days and wasn't sure where to turn. Recall the original Special Relativity thought experiment: A spaceship travels at constant velocity v, moving in the positive x direction. An observer on the spaceship emits a photon directly...
  22. B

    I I say that this experiment confirms Schrodinger's Cat....

    I'm having a fun little argument with my wife, about an article posted on www.sciencedaily.com. I say that the article CONFIRMS that Schrodinger was RIGHT. My WIFE says that this confirms that Schrodinger is WRONG. The article concerns the quantum techniques used creating the shortest pulse of...
  23. A

    Why are there modes in cantilever beam oscillation equations

    I'm doing an experiment measuring the relationship between length of a cantilever beam and period of oscillation when I twang it on one end, but I can't seem to understand the equation. The equation for measuring frequency is given here:https://www.hindawi.com/journals/amse/2013/329530/ but I...
  24. M

    Calculating Magnetic Field from FFT Amplitude

    So a little bit of background: I work in an undergraduate lab at UMass Amherst and am currently building/optimizing a faraday magnetometer for use in the Muon g-2 experiment at Fermilab. The magnetometer works as follows. A laser is shone through a crystal with a particular Verdet Constant at...
  25. N

    Double slit experiment with a glass-covered slit of unknown n

    Homework Statement A double-slit experiment uses a helium-neon laser with a wavelength of 633 nm and a slit separation of 12mm. When a thin sheet of glass is placed in front of one of the slits, the interference pattern shifts by 5 fringes. When the experiment is repeated under water, the shift...
  26. donavi

    I The spin of the photon -- a weird experiment with a laser

    Hello everybody, I'm playing with a ne -ne laser And i conducted an interesting experiment I did colliding beams the type of interferometer Fabry Pero between the mirrors I put the cuvette with different substances I tried to detect changes of polarization of the laser beam with the help of a...
  27. Paulo Figueiredo

    B Michelson-Morley Exp: Surprise of Result

    Hello! Why the surprise in the result of the Michelson-Morley experiment? If the mirrors were in earth, i think that the system is a galileu system. If the Earth is moving or if the Earth was not moving the result, in my opinion, were the same.
  28. T

    I Galileo's experiment and a lack of understanding....

    Could anyone offer me a little help with understanding why the principles demonstrated in Galileo's (probably fictional, I know) experiment involving two spheres of the same mass from a tower don't apply in the following situation please? As I understand it, the principle is essentially that...
  29. Maaruk

    I Time Dilation: Hafele-Keating Experiments

    Hi, I went ahead and read through all the similar discussions and none are on this particular topic so I'll go ahead and shoot. I did find this topic as well, but my question is pretty simple. I think I understand how time dilation works, I read through the explanation here, this jives with the...
  30. NihalRi

    Effect of mass on skid distance of car experiment

    Homework Statement I know this is long, but that is only because this question requires me to be thorough, conceptually I think it isn't difficult. To make it easier to read I bolded the important parts. In Physics lab, we were told to conduct an experiment to investigate the effect off mass...
  31. Jens Lundell

    B Electron in the double-slit experiment

    Newbie here: Is the (single) electron leaving the "machine" in the famous double-slit experiment the same one hitting the screen? Please give a short explanation on how this is proved, thank you.
  32. S

    I Exploring the Experiments & Interpretations of Quantum Physics

    If you were to explain what quantum physics is by first introducing the historic experiments/observations undertaken by scientists and then explain the different possible accepted interpretations and theory... How many experiments would you need at least? Which ones? Double Split Experiment...
  33. M

    Unraveling the Mystery of "Floating Rule" in an Experiment

    Today I was leading my students in an experiment that would reveal "the rule for what floats." We had previously floated (or sank) various objects in regular, room temperature tap water. I then weighed out 100 grams each of sugar and water, mixed them together and weighed them again. To my...
  34. M

    I Double slit experiment in 3 dimensions?

    Has anyone performed the double slit experiment in three dimensions? By this I mean, having double slits and a detection screen on three sides? This would imply there are 6 slits and 3 detection screens. What would we observe? Would we see the electron exhibiting wave like behavior (ie...
  35. Auto-Didact

    A Experiments probing the macroscopic limits of QM

    This thread is to serve as both a compilation and ground of discussion of key experiments, both historical and planned, which attempt to probe possible macroscopic limits of QM, taking into account e.g. some particular gravitational/optical/mechanical/superconducting/etc aspect and/or...
  36. M

    B Double slit experiment wave collapse

    I would like to ask this question. In the double slit experiment on wave particle duality of photon, we know that the wave function collapses and the photon behave like a particle whenever we peek. Has anyone ever placed a second double slit behind the detector to see whether a particle regain...
  37. N

    Double Slit experiment separation

    Homework Statement A double-spit experiment is performed with light of wavelength 600 nm. A wide viewing screen is 2m behind the grating. What is the distance between the two m=2 bright fringes on the screen? The slit separation given is 0.1 mm. Homework Equations Given the wavelength and...
  38. Viopia

    B Double slit experiment -- consciousness and information

    I am not a physicist but I am interested in the double slit experiment and would like a definitive answer, from a physicist, to my question as follows:. If the which path is just detected by a detector, without it flashing and bleeping at the same time, and without the detections being recorded...
  39. S

    I Explain the orbital physics of the JAXA Tether experiment?

    How is the JAXA tether experiment supposed to work in space? I hear the words, "it will act as a drag and cause early de-orbit". However, the tether is orbiting with the satellite (ATV) - same orbit, same speed (velocity), but with less mass and less drag profile than the Host Transfer Vehicle...
  40. Y

    I Double slit experiment questions

    I have a question on a particular version of the double slit experiment (I know there are many). I am not sure I understood it correctly, so I am going to explain it in a very basic manner and in my own words. You tell me if my explanation is correct or not, and then I have another question...
  41. Buzz Bloom

    I What's currently going on with the KATRIN experiment

    Does anyone know what's currently going on with the KATRIN experiment. I remember from discussions sometime last year that KATRIN was expected to have a result for the average mass of three kinds of neutrinos by the end of 2016. I just looked at the KATRIN site and there are no listed...
  42. SuchBants

    Problem graphing Irradiance and distance experiment

    Homework Statement Used a solar cell and a ray box, altering the distance from the solar cell to the light source in 10cm increments. Did the usual high school experimental controls and repeats. Assuming that the voltage is proportional to the irradiance, I am meant to graph the results...
  43. C

    Wind Turbine Blade Experiment: What is the Optimal Number for Maximum Voltage?

    Not really a homework question but this is probably the best place to post it. I'm interested in what people think about the following experiment and the wording of one of the follow up questions that came with it. It was set as part of UK GCSE Physics coursework for the 14-15 age group. 1...
  44. H

    An experiment using a diffraction grating with

    Homework Statement An experiment using a diffraction grating with a monochromatic light source is performed to create an interference pattern on a screen. Consider the following changes: I. Increase the line density of the grating. II. Decrease the frequency of the source. III. Increase...
  45. wolram

    B Double slit experiment for layman

    In the literature we are told that the double slit experiment works but are given no description of the experiment apparatus How big are the slits, how far apart are they, or does it matter Would using 3 slits make a difference, would photon go through A and B, or through B and C, or all 3. When...
  46. Robertphysics

    Superconducting motor thought experiment/ questions

    I am sorry but this question I have described is a long one. Ok so before I start a quick background , I have read and understand the Meissner effect of the superconductor expelling it’s magnetic field , also I understand that superconductor has zero resistance so a once induced or applied...
  47. N

    Interesting experiment about the attraction between two magnets

    We know that the attractive force between the opposing poles of identical permanent magnets is a product of their field strength and that the total force diminishes as the distance between them increases. If we assumed the magnets to be point entities, the formulation is the same as that for...
  48. A

    B When was the first double slit experiment done using a detector?

    When was it first experimentally seen that particle detectors can change the interference pattern effect expected in a double slit experiment? Is it still theoretical? What were some double slit experiments in the early era of quantum mechanics? How were they handled?
  49. pittsburghjoe

    I Criss-cross multiple double slit experiment paths?

    Has someone attempted to criss-cross multiple double slit experiment paths? The purpose would be to mix paths of observed and free particles. I want to know if clumps and fringes appear everywhere or we would get something new.
  50. K

    A Thought experiment: How to find Chronons?

    Hi! We were recently discussing if time appears quantified. I found the theory about "chronons" (quantums of time) on Wikipedia and I know, those are very theoretical constructs and as far as I found out there is no current research if chronons even exist. But I was wondering if somebody has an...
Back
Top